How to Care for Lilac Bushes

 

Keeping lilacs strong, healthy and blooming season after season, requires some maintenance. Proper care includes deadheading, pruning out old, diseased wood and in some severe cases, rejuvenation pruning. Deadheading involves removing the spent blossoms from this year's bloom.  This should be done as soon as possible after the flowers fade. Lilacs bloom on old wood. This means that soon after flowering, they begin to set the buds for next season's blooms. If you wait too long, you'll remove most of next years blooms.  

                      

The old flower cluster should be cut off at its base, just above the two fresh shoots that emerge from the same branch as the faded flowers. While you’re at it, cut of any old seed pods. The new shoots will grow over the summer, set flower buds and be topped off with a flower cluster the following spring. This is also the time to get rid of dead, damaged or diseased stems, as well as any branches that cross one another. To keep your lilac bush from growing too tall, remove one-third of any old stems that are thicker than two inches. Examine the base of the lilac. You’ll typically find a number of new shoots growing around the base. Remove all but three or four of this new growth. These actions will help keep the best wood and prevent the bush from getting too leggy. Prune off any extra-long stems back to the closest set of side shoots. If indeed, your lilac has seen better days, rejuvenation pruning may be in order. This involves cutting every cane back to 4”- 6” above the ground. This drastic approach will result in many vigorous canes the following season. If your lilac bush is of the grafted variety, be sure and cut above the graft. 

These care instructions are for common lilacs (Syringa vulgaris). Dwarf lilacs such as ‘Miss Kim’ seldom need pruning, other than deadheading as the blooms fade.  Finally, work in 2” of Earth Essentials sheep, peat and compost to the soil around the bush; add a balanced fertilizer, such as 11-15-11 and mulch to about 3”. Your lilac will be prepared for the rest of the summer and ready to bloom next spring.